(a) Technical Field
The present invention relates to a method for manufacturing a soundproofing material composition by recycling polyurethane foam in a discarded car seat.
(b) Background Art
In general, a soundproofing material is used in a hood insulation pad or dash insulation pad around a car engine compartment or in interior parts such as the trunk, under the hold or in the dash isolation pad, etc., where soundproofing is required.
As a typical soundproofing material in automobiles, polyethylene terephthalate (PET), fiber materials or urethane foam are frequently used. Car seats, which are usually discarded entirely without recycling, often contain thermosetting polyurethane foam that is used to provide cushion support in the seats. Since the seat foam is composed of a thermosetting material, it is not often recycled but buried underground or incinerated, causing soil and air pollution. However, there is no commercially available method for recycling the polyurethane foam from the discarded seat or for preparing a soundproofing material with satisfactory appearance quality or soundproofing performance for application in car soundproofing parts from the discarded seat foam.
Overseas, Toyota has developed recycled sound proofing products (RSPP) and used them in their automobiles in the Japanese automotive market, Raum, since 2002. However, these soundproofing products are not pure polyurethane (PU) foam but simple chipboard-type products wherein fibers and plastics are mixed. Therefore, they are of very low grade in terms of technique and quality. When considering the overall qualities of these products, including odor, VOCs, density, soundproofing performance and appearance, there is a need in the industry to provide a method for recycling discarded seat foam and producing a high quality soundproofing therefrom.